Billy longs to believe in Santa Claus, but he finds it quite difficult to do so. His family has a dogged insistence that all of it, from the North Pole, to the elves, to Santa himself, is all just a myth. This all changes, however, on Christmas Eve, when a mysterious train visits Billy in the middle of the night, promising to take him and a group of other lucky children to the North Pole for a visit with Santa. The train's conductor, along with the other passengers help turn Billy's crisis of faith into a journey of self-discovery.